The present invention relates to a power supply system. More specifically, the present invention relates to a power supply system for charging through a connector that conforms to the USB Type-C (registered trademark) standard.
The USB Type-C standard, which is a standard for next-generation USB (Universal Serial Bus) connectors, is expected to be widely used in the future in markets. As method and system for charging next-generation secondary batteries using a connector that conforms to the USB Type-C standard (Non-Patent Document 1: Universal Serial Bus Type-C Cable and Connector Specification Revision 1.2 Mar. 25, 2016), a standard called USB Power Delivery (hereinafter, referred to as PD) is established (Non-Patent Document 2: Universal Serial Bus Power Delivery Specification Revision 3.0, Vl.0a. 25 Mar. 2016). In PD, the power that can be supplied significantly increases by up to 100 W from 7.5 W (5 V, 1.5 A) of the USB battery charging standard, which is called USB Battery Charging Specification 1.2 (hereinafter, referred to as BC 1.2). More specifically, in PD, supplying a voltage higher than 5 V (more specifically, 12 V, 20 V) is allowed as a bus voltage VBUS through a VBUS line. In addition, supplying a charging current greater than BC 1.2 (more specifically, 2 A, 3 A, 5 A) is also allowed.